Opposed disc type ball projecting device

ABSTRACT

A ball throwing device having a pair of counter rotating discs which have a converging gap between so that when a ball is positioned therebetween the counter rotating discs will engage the ball and project it. The discs are mounted on separate supports which are pivotally mounted relative to each other. The supports are pivotal about vertical axis through links that are caused to move by a manually operated screw.

United States Patent [191 Cleary et al.

[ Oct. 23, 1973 1 OPPOSED DISC TYPE BALL PROJECTING DEVICE [76] Inventors: Robert A. Cleary; Paul R. Mort, Jr.,

both of 0/0 Tenni-Pro Corp., 286 Nepperhan Ave., Yonkers, NY. 10701 221 Filed: Jan.3l, 1972 211 Appl. No.: 221,911

[52] U.S. Cl 124/1, 273/26 D, 273/29 A, 124/48 [51] Int. Cl. F41b 3/04 [58] Field of Search 124/1, 49, 48, 50; 222/16; 66/146; 197/151, 273/26 D, 29 A [56] References Cited UNITED STATES PATENTS 3,399,660 9/1968 Swartoat ..124 s0x 1,743,576 1/1930 Smith 124/49 X 2,716,973 9/1955 Desi 124/1 1,501,297 7/1924 Anderson... 222/216 3,223,222 12/1965 Parker 197/151 2,918,915 12/1959 Doeg i. 124/1 Primary Examiner-Richard C. Pinkham Assistant Examiner-William R. Browne Attorney-D. C. Roylance et a1.

[57] ABSTRACT A ball throwing device having a pair of counter rotating discs which have a converging gap between so that when a ball is positioned therebetween the counter totating discs will engage the ball and project it. The discs are mounted on separate supports which are pivotally mounted relative to each other. Thesupports are pivotal about vertical axis through links that are caused to move by a manually operated screw.

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OPPOSED DISC TYPE BALL PROJECTING DEVICE This invention relates to a ball throwing machine and more particularly it relates to an improved form of ball throwing machine wherein the ball speed and the ball trajectory can be selectively adjusted and wherein the ball direction can be controlled. i

A ball throwing machine of this general type has been disclosed in U.S. Pat. No. 3,399,660, issued Sept. 3, 1968, to E. Swartout. In such prior patent, there was disclosed a pair of rotatable discs mounted at an angular relationship with respect to one another so that the axes of rotation of the discs intersected in the gap intermediate the discs while the planes of the discs intersected outside the peripheries thereof. As a result, the discs formed a converging gap into which a ball feeding device could introduce balls, one at a time. Because of the rotation of the discs, each ball was held between the discs as such discs rotated and the ball was hence carried with the discs from its point of introduction into the gap therebetween to the point where the discs diverged sufficiently so that the ball could be released and propelled forwardly.

While the ball throwing machine in the aforementioned issued patent did represent a considerable advance over what was previously known in the art, and did represent a valuable form of apparatus for throwing tennis balls, it was nevertheless considered desirable and beneficial to make certain improvements in such ball throwing machine to give the same more versatility so that it could be more readily used with other forms of balls, such as baseballs and softballs.

In view of the foregoing, it should be apparent that the main objective of the present invention is to improve upon the ball throwing machine described in the aforementioned patent, to provide a ball throwing machine with greater versatility and to provide a ball throwing machine in which the ball speed and the ball trajectory can be independently and selectively adjusted.

Another object of the present invention is to provide a ball throwing machine having an improved ball feeding device therein for assuring a more positive ball feed to the ejecting discs.

Another object of the present invention is to provide a ball throwing machine which can throw a curve ball.

Another object of the present invention is to provide an improved ball feeding machine which is rugged and durable in construction, which is capable of extended periods of operation without maintenance or repair, and which can be mass produced relatively inexpensively.

Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment thereof.

Referring tothe drawings which form apart of this original disclosure:

FIG. 1 is a top plan view of the interior of the ball throwing machine of the present invention;

FIG. 2 is a sectional view thereof taken along the line 2-2 of FIG. 1;

FIG. 3 is a front elevational view looking along the line 3-3 of FIG. 2;

FIG. 4 is a sectional view taken along the line 44 of FIG. 3;

FIG. 5 is a perspective view of the overall machine;

FIG. 6 is a top plan view of a modified motor mount and disc drive arrangement;

FIG. 7 is a sectional view of a modified disc; and

FIG. 8 is a diagrammatic view of a baseball pitching arm simulation.

Referring first to FIG. 5, the ball throwing machine shown therein is generally designated 10 and includes an exterior casing 12 within which a main frame generally designated 14, as shown in FIGS. 1-4 is enclosed. Four rigid legs 16 depend from the main frame with two of such legs carrying fixed wheels 18 and the other two legs carrying castertype wheels 20. As a result, the machine 10 can be rolled along the ground and hence transported to any desired position. The top of the casing 12 is open and is circumscribed by four side walls 22 which define therewithin a hopper. The bottom wall 24 of the hopper tapers downwardly and inwardly from each of the corners where the walls 22 intersect with one another. In the center of the bottom wall 24 a circular opening 26 is formed. As a result, when a basket full of balls is poured into the hopper, such balls will gravitationally tend to feed downwardly and inwardly along the bottom hopper wall 24 and toward and through the opening 26. A ball feeding magazine generally designated 28 is located beneath the opening 26 and inside the casing 12 and hence as the balls drop through the hole 26 they enter the magazine 28. Referring now to FIGS. 1-3 for the details of the magazine 28, it will be seen that such magazine is formed by concentrically arranged inner and outer rings 30 and 32 respectively. A series of radially extending webs 34 rigidly interconnect these inner and outer rings 30 and 32 and each adjacent pair of webs 34 sets off therebetween a pocket 36 which is open at. both the top and the bottom. A cone 38 is mounted atop the inner ring 30 and the point of the cone extends upwardly through the opening 26 in the hopper bottom wall. The purpose for this cone 38 is to make certain that the balls from the hopper are agitated and properly feed into the pockets 36 in the magazine. T

Referring for a moment to the main frame l4, it can be seen that such main frame includes an upstanding wall portion 40 and a bottom wall portion 42. A fixed ball support 44, as can best be seen in FIG. 1, is formed generally in the form .of a circular :ring whose diameter is larger than that of the inner magazine ring 30 but smaller than that of the outer magazinering 32. As a result, the ball support ring 44 extends beneath the open pockets 36 and intermediate the inner and outer rings 32 so that when a ball is carried in the pocket 36, it rests upon the ball support ring 44 in the manner shown in FIG. 2. Instead of being a continuous circular ring, however, the ball support 44 is provided with an opening of approximately the width of one pocket 36, such opening being formed between a pair of straight legs 46 which extend back'to and are connected to the upstanding wall portion 40 of the main frame. A cover plate 48 also attaches to the upstanding wall portion 40 of the main frame, and such cover plate overlies the magazine 28 above the opening formed between the legs 46 of the ball support ring 44. As a result, it can be seen that all pockets 36 in the magazine except one are open at the top but closed at the bottom by the ball support ring 44. That one pocket 36 which is open at the bottom, due to the interruption in the ball support ring, is covered at the top by the cover plate 48.

A drive means must be provided for rotating the magazine 28 to serially feedthe balls to the opening between the pair of legs 46 in the ball support ring so that such balls can gravitationally drop out of the pockets 36. To provide such drive means, it must first be noted that the ball support ring is provided with a central hub 50. The magazine is provided with a stub shaft 52, as shown in FIG. 2 and FIG. 3, which projects through the hub 50 and hence rotatably mounts the magazine 28 on the ball support ring 44. A pully 54 is fixed upon the stub shaft 52 and a drive belt 56 is trained between the pulley 54 and another pully 58 which, in turn, is attached to a magazine drive motor 60 as shown in FIG. 3. The magazine drive motor 60 is supported by a plate 62 attached to the upstanding frame portion 40 and hence as the motor 60 rotates, the drive belt 56 rotates the pully 54 and the shaft 52 and the magazine 28 connected therewith. In order to maintain proper tension on the drive belt 56 to prevent slippage, an arm 64 is provided at one end with a pivot mount 66, connected either with the plate 62 or the upstanding frame portion 40, as shown in FIG. 1, and at its other end is provided with a roller 68 which bears against the drive belt 56. To maintain the proper pulling tension on the arm 64, a tension spring 70 is connected between an aperture intermediate the ends of the arm 64 and another aperture in the plate 62, as shown in FIG. 1.

In order to receive the ball once it has been discharged from the magazine, an inclined chute 72, preferably formed in an arcuate fashion as shown in FIG. 2, is provided with its upper end 74 disposed beneath the open pocket in the magazine and its lower end 76 disposed adjacent the gap between the ball feeding discs. The inclined chute 72 is swingably mounted, as by means of a pivot mount 78 adjacent its upper end so that the attitude or elevation of the lower end 76 can be varied. To accomplish such variation or adjustment, a link 80 is attached to the side of the chute 72 and is further attached to some suitable form of adjustment means. In the illustrated embodiment, the adjustment means is formed as a screw 82 which extends through the main frame and terminates in a hand knob 84 outside the casing 12, as shown in FIG. 5.

Referring nowto the ball feeding discs, it will be seen that two such discs 86 are provided. The discs are arranged relative to one another in such a manner that the gap between them converges downwardly and inwardly, and the general orientation of the discs 86 can be considered similar to the orientation of the discs shown in the aforementioned Swartout patent. Each disc 86 is attached to a driving motor 88, as shown in FIGS. 1 and 3 and the driving motors themselves are attached to mounting blocks or support blocks 90. The blocks 90 are pivotally mounted by means of a pivot mounting 92 to the base portion 42 of the main frame. As a result, the support blocks 90, the motors 88 attached thereto and the discs 86 attached to the' motors can be pivotally moved about the axis of the pivot mount 92. In order to accomplish such movement which, in turn, will accomplish adjustment of the gap between the discs 86, a pair of links 94 are provided, as best shown in FIG. 4. Each link 94 has one end pivotally attached at 96 to the underside of a mounting block 90. The other end of the two links is interconnected together by means of a common pivot 98 which connects with a block 100. Hence, as the block 100 is moved forwardly or rearwardly, the links 94 are spread apart or closed together and hence the mounting blocks are pivoted about their pivot mounts 92. In order to accomplish such motion of the links 94, the block can be attached to some suitable adjustment means which, in the illustrated form, consists of an elongated screw 102 which threads through the main frame and terminates in a knob 104 located outside the casing 12, as shown in FIG. 5.

As also shown in FIG. 5, a control box 106 is attached to the exterior of the machine casing 12 and such control box is provided with a series of manually adjustable controls generally designated 108. At least one of the controls operates the magazine drive motor 60 which is a variable speed motor.'By proper adjustment of this control, the rotational rate of the magazine 28 can be selectively varied, and accordingly, the ball ejection rate can be adjusted. For example, if it is desired to have the machine throw one ball every 15 seconds, then the control would be set for this rate. If it was desired to have the balls thrown more frequently or less frequently, such adjustment could also be made.

While the adjustments for the chute and discs have been shown as knobs 84 and 104, respectively, attached to threaded adjustment screws, the invention need not be limited to this precise arrangement, and, if desired, adjustment levers or the like can be utilized. It is, however, important to note that the adjustments are independent of one another and that they permit the attitude of the chute 72 and the angular disposition of the discs 86 to be selectively and independently adjusted. Such adjustment permits a variation of both the speed at which the ball is ejected from the machine, and additionally, the trajectory at which the ball is ejected. Specifically, by adjustment of the attitude or elevation of the lower end of the chute 72, it is possible to vary the length of time in which the ball is carried between the rotating discs 86. If the lower end 76 of the chute 72 is at or near its uppermost position, then the ball can be carried between the discs for a considerable arc, for example, an arc of 90. On the other hand, if the end 76 of the chute is near its lowermost position, then the ball will only be carried between the discs for a short time, for example, an arc of 15. The longer the ball is carried between the discs, the greater the centrifugal speed at which the ball will be ejected from the discs and hence the faster the ball will travel once it is ejected or propelled outwardly from the machine. Thus, adjustment of the chute 72 accomplishes an adjustment of the ball ejection speed. On the other hand, adjustment of the discs 86 by means of pivoting the disc mounting blocks 90 through action of the links 94 accomplishes an adjustment of the trajectory of the ball. In this regard, it must be recognized that the ball will only be carried between the two discs 86 so long as the gap therebetween is smaller than the diameter of the ball. Once the gap reaches a size which is greater than the ball diameter, then the ball is released from engagementwith the discs and propelled forwardly. Therefore, if the discs are adjusted so that the gap opens rapidly so that the ball will not be carried much further than the lowermost or bottom dead center of the discs, then the ball will be propelled forwardly at a relatively low elevation. On the other hand, if the discs are adjusted so that the gap stays together until the ball is carried forwardly and upwardly for a considerable distance, then the ball will be propelled high into the air with a relatively high trajectory.

It may be desirable to use the machine of the present invention as a tennis practice machine, for throwing tennis balls, and in such event, the discs 86 need no covering material, since the material of the tennis balls can frictionally engage against even a plain metal surface on the discs 86. However, when the machine is used for throwing a baseball, there may be a tendency for the smooth material of the ball to slip relative to the smooth metal of a disc 86, and accordingly, it is useful to apply a rubber or plastic coating to the discs 86 to make certain that the baseball will be frictionally en gaged against such coating and cannot slip relatively thereto. In FIG. 7, the disc 86 is shown with such a rubber or plastic coating 120 adhered or attached to the front surface thereof. A mounting ring or plate 122 helps assure that the coating 120 remain fixed in position. The front surface of the coating 120 can be flat, having no angle whatsoever, or it can be angled as shown by the letter X in FIG. 7. The angle X can be varied, as desired, depending upon whether the ball is to be thrown overhand or underhand, whether it is a hardball or a softball, and so on.

When the machine is to be used for pitching baseballs, it obviously will be desirable to throw curve balls to let a batter get practice hitting such curve balls. In FIG. 6, there is illustrated one satisfactory arrangement for enabling the machine of the present invention to throw curves. The arrangement of FIG. 6 includes the discs 86, their driving motors 88 and the mounting or support blocks 90 for the motors. However,'unlike the arrangement shown in FIG. 1, the motors 88 include a pair of side flanges 124, each of which includes a pair of laterally elongated slots 126 formed therein. Bolts 128 extend through the slots 126 and into the support blocks 90. When the bolts 128 are tightened, they press washers 130 against the flanges 124 to lock the motor, and its attached disc, in position on the support block 90. lnthe arrangement shown in solid lines in FIG. 6, both motors 88 and their discs 86 are coaxially aligned along a centerline C. To throw a curve ball, the bolts 128 are loosened on one motor and such motor is moved until it reaches the position shown in dotted lines, wherein its centerline C isfrom the centerline C. Then, the bolts are again tightened and because of the offset relationship of the motors and discs, the ball will be thrown with a curve.'Depending upon which motor is moved, the machine will throw either an inside curve or an outside curve. Thatis, let it be assumed that the dotted line position of the lower motor and disc in FIG. 6 will cause the machine to throw an inside curve,

. namely, a curve ball which breaks inwardly toward the batter. Thus, if the lower motor in FIG. 6 is left in its solid line position and the upper motor and disc are displaced, then the machine will throw an outside curve, namely, a curve ball which breaks outwardly and away from the batter. It is, of course, possible to use other arrangements for accomplishing the curve ball effect, such as having each support block 90 attached to a lead screw which could move such block, and the motor and disc attached thereto, forwardly or rearwardly. However, the principle involved, and the manner in which a curve is imparted to the ball, would remain the same.-

Finally, in FIG. 8 there is shown a further modification which can be used for sharpening a batters timing. In FIG. 8, a false arm 132 is provided with a false hand 134 which holds a ball 136. The arm is pivotally mounted about a pivot 138. The arm can be mechanically or electrically connected, as shown schematically at 140, to a sensing device 142 such as a microswitch on the chute 72. The arm is nonnally disposed rearwardly, as shown in solid lines, but whena ball is delivered through the chute to the discs, itcan swing forwardly through an arc as the ball B is discharged forwardly from between the discs 86. It thus appears to the batter as if the arm 132 is throwing the ball 136 whereas, in fact, it is the ball B being thrown. Movement of the arm 132 can be accomplished by any suitable driving device such as a rack and pinion, electric motor, belt drive, mechanical linkage, or the like.

As a result of the improvement of the present inven tion, which enables both the ball speed and the ball trajectory to be selectively adjusted, the machine of the present invention offers a unique and useful ball throwing device for such purposes as baseball training. Not only can the machine be used for batting practice, but it can also be used for fielding practice. In batting practice, the machine can throw high balls, low balls, strikes and fast pitches as well as slow pitches. Because the machine permits ball direction control, curve ball pitches can also be thrown. For fielding practice, the machine can throw ground balls, high fly-balls, pop flys, and anything in between.

After reading the foregoing detailed description, it should be apparent that the objects set forth at the outset of the specification have been successfully achieved by the present invention.

Accordingly what is claimed is: 1. In a ball-throwing machine of the type having a pair of rotatably mounted discs which form therebetween a converging gap into which a ball can be introduced, the improvement which comprises:

a rotatably mounted magazine having a plurality of openings extending therethrough to form pockets for receiving balls to be thrown:

a chute having its upper end disposed adjacent said magazine for gravitationally receiving a ball from a pocket in said magazine and having its. lower end disposed adjacent said converging gap fordischarging a ball betwen said discs; 1

means for supporting said pair of discs;

first adjustment means connected with said chute to permit selective adjustment of said chutes lower end relative to said converging gap; second adjustment means connected with said disc supporting means to enable said discs to be selectively adjusted relative to one another to vary said converging gap,

said disc supporting means including a drive motor for each one of saiddiscs, a mounting block for each drive motor and,

a pivot mount for each one of said mounting blocks; said second adjustment means including means connected with each of said mounting blocks to enable each one of said block to be pivoted about its respective pivotal axis.

2. The improvement defined in claim 1 wherein said magazine is rotatable about a central axis, wherein said disc supporting means are rotatable about, and wherein all such axes are substantially parallel to one another.

3. The improvement defined in claim 1 wherein the magazine has a ball receiving pocket, a fixed ball support is disposed beneath said magazine so that a ball within said .pocket rests upon said ball support as said magazine rotates.

4. The improvement defined in claim 3 wherein said ball support is interrupted at the area overlying said chute upper end so that a ball can drop gravitationally from said pocket into said chute, and wherein a cover overlies said magazine above the interrupted area of said ball support.

5. The improvement defined in claim 1 wherein a drive means is provided for rotating said magazine, said drive means including a drive motor positioned remotely from said magazine, a drive belt connected between said drive motor and said magazine, and a spring biased arm exerting pressure against said drive belt between said drive motor and said magazine for maintaining tension on said drive belt.

6. The improvement defined in claim 1 wherein the means connected with each one of said mounting blocks includes a pair of links, one of which is pivotally connected with each mounting block.

7. The improvement defined in claim 1 wherein said discs have a slip resistant coating on the surfaces thereof facing said gap.

8. The improvement defined in claim 1 wherein means are provided to enable at least one of said discs to be moved relatively to said chute lower end and to said other disc so that a curve will be imparted to a ball thrown by said discs.

9. In a ball throwing machine of the type having a main frame, a pair of discs mounted in such relative positions that the axes of said discs shall normally intersect at a point midway between said discs and that the planes of such discs shall intersect at a point outside the peripheries of said discs, means for rotating said discs and means for introducing a ball between said discs while said discs are rotated so that the ball shall be ejected at a high rate of speed, the improvement wherein:

said means for introducing a ball between said discs comprises a magazine formed by spaced concentric inner and outer rings having radial webs extending therebetween forming a series of ball receiving pockets,

a ball support means fixed beneath said magazine to support the balls within said pockets, said ball support means having an opening to enable a ball to drop gravitationally from one pocket and through said opening, and

an inclined chute having an upper end adjacent said opening in said ball support means and having a lower end extending between said pair of discs so that a ball dropping from one of said pockets and through said opening will pass through said chute and discharge between said discs;

said means for rotating said discs comprises a drive motor fixed to each of said discs;

a mounting block is provided for each of said drive motors, each one of said mounting blocks being pivotally attached to said main frame;

a first attachment means is connected to said inclined chute to permit selective adjustment of the angle of inclination of said chute; and

a second attachment means is connected to said mounting blocks to permit selective pivoting of said mounting blocks and hence to permit adjustment of said relative positions of said discs.

10. The improvement defined in claim 9 wherein said magazine further includes a cone mounted upon said inner ring to facilitate flow of said balls into said pockets.

11. The improvement defined in claim 9 wherein a drive means is provided for rotating said magazine, said drive means including:

a magazine drive motor attached to said main frame,

a drive pulley attached to said magazine drive motor,

a driven pulley attached to said magazine,

a belt drive trained over said drive pulley and driven pulley, and

a spring biased arm exerting pressure against said belt drive to maintain tension thereon.

12. The improvement defined in claim 9 further including means for adjusting the position of each drive motor on its mounting block to permit one drive motor and its associated disc to be moved to a position where the disc axes are out of their normal intersecting alignment, whereby a curve is imparted to a ball thrown by said discs.

13. The improvement defined in claim 9 further including an arm member swingably mounted above said discs, said arm member being swung forwardly as a ball is thrown by said discs to simulate a ball being thrown by said arm member. 

1. In a ball throwing machine of the type having a pair of rotatably mounted discs which form therebetween a converging gap into which a ball can be introduced, the improvement which comprises: a rotatably mounted magazine having a plurality of openings extending therethrough to form pockets for receiving balls to be thrown: a chute having its upper end disposed adjacent said magazine for gravitationally receiving a ball from a pocket in said magazine and having its lower end disposed adjacent said converging gap for discharging a ball betwen said discs; means for supporting said pair of discs; first adjustment means connected with said chute to permit selective adjustment of said chute''s lower end relative to said converging gap; second adjustment means connected with said disc supporting means to enable said discs to be selectively adjusted relative to one another to vary said converging gap, said disc supporting means including a drive motor for each one of said discs, a mounting block for each drive motor and, a pivot mount for each one of said mounting blocks; said second adjustment means including means connected with each of said mounting blocks to enable each one of said block to be pivoted about its respective pivotal axis.
 2. The improvement defined in claim 1 wherein said magazine is rotatable about a central axis, wherein said disc supporting means are rotatable about, and wherein all such axes are substantially parallel to one another.
 3. The improvement defined in claim 1 wherein the magazine has a ball receiving pocket, a fixed ball support is disposed beneath said magazine so that a ball within said pocket rests upon said ball support as said magazine rotates.
 4. The improvement defined in claim 3 wherein said ball support is interrupted at the area overlying said chute upper end so that a ball can drop gravitationally from said pocket into said chute, and wherein a cover overlies said magazine above the interrupted area of said ball support.
 5. The improvement defined in claim 1 wherein a drive means is provided for rotating said magazine, said drive means including a drive motor positioned remotely from said magazine, a drive belt connected between said drive motor and said magazine, and a spring biased arm exerting pressure against said drive belt between said drive motor and said magazine for maintaining tension on said drive belt.
 6. The improvement defined in claim 1 wherein the means connected with each one of said mounting blocks includes a pair of links, one of which is pivotally connected with each mounting block.
 7. The improvement defined in claim 1 wherein said discs have a slip resistant coating on the surfaces thereof facing said gap.
 8. The improvement defined in claim 1 wherein means are provided to enable at least one of said discs to be moved relatively to said chute lower end and to said other disc so that a curve will be imparted to a ball thrown by said discs.
 9. In a ball throwing machine of the type having a main frame, a pair of discs mounted in such relative positions that the axes of said discs shall normally intersect at a point midway between said discs and that the planes of such discs shall intersect at a point outside the peripheries of said discs, means for rotating said discs and means for introducing a ball between said discs while said discs are rotated so that the ball shall be ejected at a high rate of speed, the improvement wherein: said means for introducing a ball between said discs comprises a magazine formed by spaced concentric inner aNd outer rings having radial webs extending therebetween forming a series of ball receiving pockets, a ball support means fixed beneath said magazine to support the balls within said pockets, said ball support means having an opening to enable a ball to drop gravitationally from one pocket and through said opening, and an inclined chute having an upper end adjacent said opening in said ball support means and having a lower end extending between said pair of discs so that a ball dropping from one of said pockets and through said opening will pass through said chute and discharge between said discs; said means for rotating said discs comprises a drive motor fixed to each of said discs; a mounting block is provided for each of said drive motors, each one of said mounting blocks being pivotally attached to said main frame; a first attachment means is connected to said inclined chute to permit selective adjustment of the angle of inclination of said chute; and a second attachment means is connected to said mounting blocks to permit selective pivoting of said mounting blocks and hence to permit adjustment of said relative positions of said discs.
 10. The improvement defined in claim 9 wherein said magazine further includes a cone mounted upon said inner ring to facilitate flow of said balls into said pockets.
 11. The improvement defined in claim 9 wherein a drive means is provided for rotating said magazine, said drive means including: a magazine drive motor attached to said main frame, a drive pulley attached to said magazine drive motor, a driven pulley attached to said magazine, a belt drive trained over said drive pulley and driven pulley, and a spring biased arm exerting pressure against said belt drive to maintain tension thereon.
 12. The improvement defined in claim 9 further including means for adjusting the position of each drive motor on its mounting block to permit one drive motor and its associated disc to be moved to a position where the disc axes are out of their normal intersecting alignment, whereby a curve is imparted to a ball thrown by said discs.
 13. The improvement defined in claim 9 further including an arm member swingably mounted above said discs, said arm member being swung forwardly as a ball is thrown by said discs to simulate a ball being thrown by said arm member. 